This invention relates to a break-away bracket and more particularly to such a bracket for use in mounting a rear view mirror on the outside of a vehicle.
Rear view mirrors of the type mounted on the exterior of a vehicle are conventionally attached to a rigid bracket which in turn is bolted to the vehicle door or fender. In the case of a truck cab for pulling a wide bodied vehicle and other wide bodied vehicles the mirror is connected to elongated arms which are secured to the bracket, the bracket being bolted directly to the door of the vehicle. If the mirror or the arms strike an external object, such as another vehicle, a tree, building etc., the moment acts to force the bracket away from the vehicle pulling the attaching bolts so that costly damage results to the vehicle body portion to which the bracket is attached.
The known relevant prior art mirror attaching brackets are those illustrated in U.S. Pat. Nos. 3,599,926 (Takahashi); 3,887,156 (Hugonnier); 4,066,235 (Hashiguchi) and 4,368,868 (Urban). Takahashi and Hashiguchi relate to the mounting of interior mirrors while Hugonnier and Urban are directed to the mounting of mirrors on the exterior of the vehicle. The Takahashi and Hashiguchi patents respectively show a break-away plastic plate interposed between an attaching base of a rear view mirror and the body of the vehicle, the plate having a groove surrounding the area where an attaching screw connects the plates to the base and breaks at the groove when a force is applied to the mirror; and a rear view mirror having a pair of plastic mirror mounting members which are connected together at a frangible portion formed by tiny holes about a central portion of one of the members, the other member together with the central portion breaking away from the first portion on impact. The Hugonnier and Urban patents respectively disclose the end of the mirror arm connected within the bore of a socket of a base secured to the vehicle, the connection between the arm and the base being through a plastic ring that separates to release the arm when the mirror is impacted; and a mirror carrying arm capable of breaking away from the hollow threaded neck of a plastic bracket when the mirror is impacted. In each of these prior art disclosures a relatively complex and expensive mirror mounting arrangement is proposed to overcome the difficulties of conventional mirror mounting brackets.